A locomotive is a complex system with numerous subsystems, each subsystem interdependent on other subsystems. An operator aboard a locomotive applies tractive and braking effort to control the speed of the locomotive and its load of railcars to assure safe and timely arrival at the desired destination. Speed control must also be exercised to maintain in-train forces within acceptable limits, thereby avoiding excessive coupler forces and the possibility of a train break. To perform this function and comply with prescribed operating speeds that may vary with the train's location on the track, the operator generally must have extensive experience operating the locomotive over the specified terrain with various railcar consists, i.e., different types and number of railcars.
However, even with sufficient knowledge and experience to assure safe operation, the operator generally cannot operate the locomotive to minimize fuel consumption (or other operating characteristics, e.g., emissions) during a trip. Multiple operating factors affect fuel consumption, including, for example, emission limits, locomotive fuel/emissions characteristics, size and loading of railcars, weather, traffic conditions and locomotive operating parameters. An operator can more effectively and efficiently operate a train (through the application of tractive and braking efforts) if provided control information that optimizes performance during a trip while meeting a required schedule (arrival time) and using a minimal amount of fuel (or optimizing another operating parameter), despite the many variables that affect performance. Thus it is desired for the operator to operate the train under the guidance (or control) of an apparatus or process that advises the application of tractive and braking efforts to optimize one or more operating parameters.